Unreal Engine Issues
Unreal Engine Issues
Section::TrimSection resulting in bad key values at start and end of trim range
UE - Anim - Sequencer - Dec 17, 2025The trim process inserts keys at the start or end of the range depending if you specify Trim Left or Right, I'm finding that Trim right is inserting a key at the end of the section that is incorrect ...
Exporting Mannequin to Blender then Re-importing to UE4 Incorrectly Rotates Animations by 90 Degrees
OLD - Anim - Jun 16, 2015Exporting the UE4 Mannequin to Blender then re-importing to UE4 breaks the animations, causing them to reimport rotated 90 degrees ...
Animation Orientation does not Auto-Convert to UE4 Coordinates when Reimporting
OLD - Anim - Nov 23, 2015Animation orientation does not auto-convert to UE4 coordinates when reimporting the same way it does when importing the same animation as a new import. In other words, a run animation generated from ...
BulkData Async loading remains in memory
UE - Foundation - Core - Oct 26, 2016Gil's new loading path may already walk away from this issue. But here's some thing I tested locally if we want to fix this. A simple way to fix is to simply add BulkDataAsync.Deallocate(); ResetA ...
Editor Crashes on Opening After Deriving C++ Class from Another Class
UE - Foundation - Cpp Tools - Hot Reload - Sep 13, 2017After deriving a C++ class from another class and then closing the editor, the project will crash when reopened. This crash will continue until the project files are regenerated and the project is r ...
[CrashReport] FLandscapeEditorCustomNodeBuilder_TargetLayers::OnTargetLayerDeleteClicked()
UE - LD & Modeling - Terrain - Landscape - Oct 5, 2017This is a somewhat common Landscape crash occurring throughout the 4.17 release. User Descriptions1) rename landscape layer, 2) delete layer in landscape tool Source Context 1307 FReply FL ...
Navmesh doesn't work in a Packaged Build if it was placed in a Sublevel
UE - AI - Oct 19, 2018Once packaged, a persistent level is unable to create navmesh data properly if the navmesh bounds volumes are only present in its sublevels. The issue can be traced to the UNavigationSystemV1::IsThe ...
AbilitySystemComponent::NotifyAbilityEnded Can Crash due to Callbacks Invalidation Specs
UE - Gameplay - Gameplay Ability System - Oct 11, 2023Pasting from the UDN: Unsafe code in AbilitySystem can lead to crash when granting an ability inside OnAbilityEnded Hello. We just ran into a crash. After investigation, it seems to be caused by ...
Timeline functions do not work inside of Blueprint functions
UE - Gameplay - Blueprint - Dec 20, 2014I could not repro their issue in main. They supposedly recently upgraded to 4.5. I was wondering if you could divide an conquer, and figure out when we fixed this. **EDIT** Was able to repro in mai ...
Crash Opening Editor with Vulkan - Fatal Error - RenderingThread.cpp
UE - Rendering - Architecture - RHI - Mar 15, 2019Editor crashes when opening to project browser on Linux. Fatal error: [File:D:\Build\++UE4\Sync\Engine\Source\Runtime\RenderCore\Private\RenderingThread.cpp] [Line: 819] Rendering thread exceptio ...